Britain held a nationwide minute of silence Tuesday to honor the victims of Saturday's terror attack in London, as police announced the name of the third attacker killed by officers and made a new arrest linked to the investigation.
Metropolitan Police said detectives believe 22-year-old Youssef Zaghba was the remaining attacker who had not yet been publicly identified. They said he is believed to be an Italian national of Moroccan descent who lived in East London, and that he had not been a subject of interest for either police or the MI5 intelligence agency.
Authorities on Monday identified the other two attackers as 27-year-old British citizen Khuram Shazad Butt and 30-year-old Rachid Redouane, who also lived in East London. Police said Butt was previously known to authorities, but had not been viewed as a serious threat.
"There was no intelligence to suggest that this attack was being planned, and the investigation had been prioritized accordingly," police said in a statement.
Counterterrorism police arrested a 27-year-old man Tuesday in the Barking area, but did not say how he might be connected to the attack that killed seven people and wounded at least 50 others.
Police had previously arrested 12 people in the course of the investigation, but said Monday those 12 had all been released without any charges.
British Prime Minister Theresa May said police also are still working to determine the identities of all the victims, but that so far it is known they include people of several nationalities.
"This was an attack on London and the United Kingdom, but it was also an attack on the free world," she said.
London Mayor Sadiq Khan said at a vigil Monday that the city "will never be broken by terrorism."
"Our unity and love for one another will always be stronger than the hate of the extremists," Khan said.
Police have said Saturday's attack involved three men who were inside a van that struck pedestrians on London Bridge, and then got out and stabbed numerous people at a nearby market area before being shot dead by police.
The Islamic State group claimed responsibility for the attack through its Amaq news agency.